Starlike energy-saving hole blasting method

Abstract

The invention discloses a starlike energy-saving hole blasting method. The starlike energy-saving hole blasting method comprises the following steps that firstly, a central main blasting hole is formed in the working surface, then five secondary blasting holes with the same hole depth are formed around the central main blasting hole, the secondary blasting holes are evenly formed around the main blasting hole according to the shape of a five-pointed star, and empty holes with the same hole depth and the same distance are formed around the main blasting hole and used as the compensation space for the hole blasting; the loading quantity of the main blasting hole accounts for 60% of the hole depth, and the loading quantity of each central secondary blasting hole accounts about 40-60% of the hole depth; and at the time of detonation, the main blasting hole firstly detonates, and the secondary blasting holes detonate in sequence. The starlike energy-saving hole blasting method combines theadvantages of a parallel empty hole straight blasting method, has the characteristics of simple operation process, fast drilling, high footage rate, low blasting cost and the like, and is suitable forvarious sections; and security risks such as roof failure can be reduced in the fracture section excavation.

Description

technical field [0001] The invention relates to a star-shaped energy-saving cutting method, which can be widely used in the blasting and excavation of underground engineering such as railway and highway tunnels, hydraulic tunnels, underground mining roadways, underground workshops and caverns, and is especially suitable for relatively broken rock masses. , Safe and efficient excavation of sections with unstable roofs. technical background [0002] The tunneling footage mainly depends on the efficiency of the cutting. The traditional cutting methods in roadway excavation are mainly oblique hole cutting and parallel hollow hole straight line cutting. Inclined hole cutting refers to the cutting method in which the direction of the cutting hole is oblique to the working surface, and is usually divided into one-way cutting, tapered cutting and wedge-shaped cutting. Parallel hole straight cut is also called straight hole cut, all cut holes are perpendicular to the working surfac...

AI Technical Summary

Problems solved by technology

The cutting eye and the excavation section of oblique cutting are obliquely intersected, which has the advantages of simple operation, lower precision requirements than straight cutting, the cutting method and cutting angle can be selected according to the actual situation of the rock formation, and it is easy to throw rocks and cut The number of boreholes is small and the consumption of explosives is low, but there are disadvantages such as difficult to control the drilling direction, the depth of the blasthole is easily limited by the size of the excavation section, it is difficult to increase the cycle footage, and it is not convenient for multiple rock drills to operate at the same time.

Although straight-line cutting with parallel holes has high blasthole utilization rate and is not limited by the section of the roadway. Fourth, it has the advantages of convenient drilling and high accuracy, but it has the disadvantages of high explosive unit consumption. The protective effect of the roof is not enough, which increases support costs and safety hazards

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